ادغام وارون‌سازی داده‌های لرزه‌ای و روابط فیزیک سنگی برای تحلیل و تعیین توزیع انواع شیل در یکی از میادین خلیج‌ فارس

نوع مقاله: مقاله تحقیقی‌ (پژوهشی‌)

نویسندگان

1 دانشکده مهندسی نفت، دانشگاه صنعتی امیرکبیر، تهران، ایران

2 مؤسسه ژئوفیزیک دانشگاه تهران، تهران، ایران

3 مدیر توسعه و تحقیق فیزیک سنگ، شرکت CGG، لاهه، هلند

چکیده

توصیف مخزن با استفاده از داده‌های لرزه‌ای که با عنوان توصیف لرزه‌ای مخزن شناخته می­شود، یکی از روش­های بهینه برای شناخت مخازن هیدروکربنی است. با توجه به نقش یکپارچه­کننده فیزیک سنگ، استفاده از آن در توصیف لرزه‌ای مخزن ضروری است. یکی از کمیت­های مخزنی مهم در توصیف لرزه‌ای مخزن، حجم شیل و به­طورکلی مطالعه شیل موجود در مخزن است. وجود فراوان شیل در ناحیه‌ای از مخزن باعث کاهش کیفیت مخزنی می­شود و باید مناطق مخزنی از مناطق غیرمخزنی تفکیک شوند؛ بنابراین با توجه به اثرهای مخربی که شیل­ها بر کیفیت مخزن دارند، شناسایی توزیع انواع گوناگون شیل­ها نیز مهم است. در پژوهش حاضر به بررسی و مطالعه شیل­های موجود در یکی از میادین غربی خلیج فارس با استفاده از فیزیک سنگ پرداخته شده است. برای تفکیک نحوه توزیع انواع شیل­ها در این میدان، از قالب­های فیزیک سنگی، نتایج وارون‌سازی توأم، مدل‌سازی تجربی فیزیک سنگی و مدل توماس و استیبر استفاده شده است. پس از بررسی­ها مشخص شد نواحی انتهایی این مخزن، حاوی شیل­های ساختاری و قسمت­های میانی حاوی شیل­های پراکنده و لایه‌ای است که باعث کاهش کیفیت مخزن می­شوند. با توجه به روش ارائه­شده در این مقاله می­توان محل توزیع انواع شیل­ها را شناسایی کرد و به­این­ترتیب به شناسایی بهتر مخزن میدان مورد نظر پرداخت.

کلیدواژه‌ها

موضوعات


عنوان مقاله [English]

Integration of seismic inversion and rock physics relationships for determining of shale distribution in one of the reservoirs in the Persian Gulf

نویسندگان [English]

  • Benyamin Khademalomum 1
  • Abdolrahim Javaherian 2
  • Mohammad Reza Saberi 3
1 Department of Petroleum Engineering, Amirkabir University of Technology, Tehran, Iran
2 Institute of Geophysics, University of Tehran, Tehran, Iran
3 Product Development Manager, Rock physics, CGG, The Hague, The Netherland
چکیده [English]

Characterization of siliciclastic reservoirs from seismic data is very sensitive to their clay and shale content. Clay can affect P- and S-wave velocities through its type and shape as well as location. Such an elastic behavior of clay infers that reservoir properties can be overlooked if their clay content is not understood and interpreted adequately. Clay can exist in different types with their specific shape and even can be distributed within siliciclastic rocks in various forms- structural, laminar, interstitial and dispersed clay- with different velocity responses. The mixture of the various clay types and forms can make their velocity interpretation for reservoir properties more complicated. Therefore, a proper strategy to separate the effects of clay types and clay forms is necessary for any seismic reservoir characterization on siliciclastic reservoirs with high clay content. Rock physics is a bridge between seismic and reservoir properties. An important goal of this branch of science is to understand the physical properties of the reservoir, so it is important for this kind of study. This study integrates rock physics modeling and simultaneous seismic inversion in order to find different clay distribution (forms) in one of the oilfields in the western part of the Persian Gulf. The well log data (wells A, B, and C) from this field show how the reservoir quality varies within the field with no obvious relationship to their shale content. This independent behavior of shale content and reservoir properties could be an indication that clay distribution may vary and clay type is not the only parameter for clay effects on the reservoir properties. Therefore, Thomas-Stieber rock physics template, first, is used to characterize shale distribution at well location and then the same template is applied on the reservoir properties derived from simultaneous seismic inversion to understand clay distribution in the whole area. Our results confirm that at wells, clay distribution is varying from top to the bottom of the reservoir. We find out that reservoir quality is not changed within the bottom part of the reservoir with high clay content (due to structural clay) while the same clay content reduced reservoir quality in the top and middle parts of the reservoir (due to the dispersed and layered clay). In order to do reservoir characterization, a map of shale content from top Ghar and top lower Asmari is generated. This generated map differentiates proper reservoir interval from the non-reservoir interval. Therefore, by using the proposed method in this study, one can delineate the potential zones of the reservoir for the future plan of drilling and production.

کلیدواژه‌ها [English]

  • seismic reservoir characterization
  • rock physics modeling
  • Thomas and Stieber model
  • simultaneous inversion

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